update: 添加问题“2787.将一个数字表示成幂的和的方案数”的代码和题解 (#1077)

* words: jp - 这个部分好多生词啊 (#1074)

* 2787: init (#1074)

* 2787: WA.cpp (#1074) - 要的是互不相同整数

这种方法每个正数可以被复用

* 2787: WA.cpp (#1074)

* 2787: MLE.cpp (#1074) - x=1时死循环

* 2787: WA.cpp (#1074) - 是t^x而不是x^t

* 2787: WA.cpp (#1074)

input: 213 1
should: 55852583
output: 1055852590
这咋还都有个558525

* 2787: WA.cpp (#1074) - 看来不是pow精度的问题

* 2787: AC.cpp (#1074) - 原来是忘取模了

cpp - AC,46.82%,36.36%
TODO: 不再单独创建个pows数组了
晚上整整转正材料复习(学习)下背包吧

* 2787: AC.cpp+WA.py (#1074) - 不预先创建pow数组

cpp - AC,82.74%,95.33%

* 2787: AC.py+WA.go (#1074)

py - AC,75.72%,50.00%

* 2787: WA.go (#1074) - 忘记取模了

* 2787: AC.go+CE.java (#1074)

go - AC,83.10%,90.14%

* 2787: AC.java+rust (#1074) - rust编译过就AC了，safe(bushi)

java - AC,98.08%,42.58%
rust - AC,57.14%,71.43%

刚刚：
1. ArrayList<>(n + 1)只是预分配空间，还需要n+1次.add(0)
2. dp.get(xxa) = xxb不可，需要dp.set(xxa, xxb)
3. long完要int回去
4. pow完也要强制转int

* fix: Mac上debug cpp后会newSolution.py读文件夹的“文本内容”失败

close #1075

* fix: Mac上debug cpp后会newSolution.py读文件夹的“文本内容”失败 (#1074)

close #1075

* update: 添加问题“2787.将一个数字表示成幂的和的方案数”的代码和题解 (#1077)
close #1074

Signed-off-by: LetMeFly666 <[email protected]>

* 2787: clean.java (#1074)

#1077 (comment)

---------

Signed-off-by: LetMeFly666 <[email protected]>

Author: LetMeFly666

.commitmsg

@@ -0,0 +1 @@
+close #1074

.vscode/launch.json

@@ -38,7 +38,7 @@
             "request": "launch",
             "program": "${fileDirname}/${fileBasenameNoExtension}",
             "args": [],
-            "stopAtEntry": true,
+            "stopAtEntry": false,
             "cwd": "${fileDirname}",
             "environment": [],
             "externalConsole": true,

.vscode/settings.json

@@ -92,7 +92,9 @@
         "queue": "cpp",
         "span": "cpp",
         "__locale": "cpp",
-        "ios": "cpp"
+        "ios": "cpp",
+        "__config": "cpp",
+        "__bit_reference": "cpp"
     },
     "editor.mouseWheelZoom": true,
     "workbench.tree.enableStickyScroll": true,

Codes/2787-ways-to-express-an-integer-as-sum-of-powers.cpp

@@ -0,0 +1,64 @@
+/*
+ * @Author: LetMeFly
+ * @Date: 2025-08-12 09:48:56
+ * @LastEditors: LetMeFly.xyz
+ * @LastEditTime: 2025-08-12 21:33:24
+ */
+#if defined(_WIN32) || defined(__APPLE__)
+#include "_[1,2]toVector.h"
+#endif
+
+// dp[i]: 和为i的方案数
+class Solution {
+private:
+    static const long long MOD = 1e9 + 7;
+
+    int pow(int a, int b) {
+        long long ans = 1;
+        while (b) {
+            if (b & 1) {
+                ans = ans * a;
+            }
+            a = a * a;
+            b >>= 1;
+        }
+        return ans;
+    }
+public:
+    int numberOfWays(int n, int x) {
+        vector<int> dp(n + 1);
+        dp[0] = 1;
+        for (int th = 1; ; th++) {
+            int p = pow(th, x);
+            if (p > n) {
+                break;
+            }
+            for (int i = n; i >= p; i--) {
+                dp[i] = (dp[i] + dp[i - p]) % MOD;
+            }
+        }
+        return dp.back();
+    }
+};
+
+#if defined(_WIN32) || defined(__APPLE__)
+/*
+10 2
+
+1
+*/
+
+/*
+4 1
+
+
+*/
+int main() {
+    int a, b;
+    while (cin >> a >> b) {
+        Solution sol;
+        cout << sol.numberOfWays(a, b) << endl;
+    }
+    return 0;
+}
+#endif

Codes/2787-ways-to-express-an-integer-as-sum-of-powers.go

@@ -0,0 +1,28 @@
+/*
+ * @Author: LetMeFly
+ * @Date: 2025-08-12 09:48:56
+ * @LastEditors: LetMeFly.xyz
+ * @LastEditTime: 2025-08-12 21:42:16
+ */
+package main
+
+import "math"
+
+func pow2787(a, b int) int {
+    return int(math.Pow(float64(a), float64(b)))
+}
+
+func numberOfWays(n int, x int) int {
+    dp := make([]int, n + 1)
+    dp[0] = 1
+    for th := 1; ; th++ {
+        p := pow2787(th, x)
+        if p > n {
+            break
+        }
+        for i := n; i >= p; i-- {
+            dp[i] += dp[i - p]
+        }
+    }
+    return dp[n] % 1000000007
+}

Codes/2787-ways-to-express-an-integer-as-sum-of-powers.java

@@ -0,0 +1,22 @@
+/*
+ * @Author: LetMeFly
+ * @Date: 2025-08-12 09:48:56
+ * @LastEditors: LetMeFly.xyz
+ * @LastEditTime: 2025-08-12 22:58:59
+ */
+class Solution {
+    public int numberOfWays(int n, int x) {
+        long[] dp = new long[n + 1];
+        dp[0] = 1;
+        for (int th = 1; ; th++) {
+            int p = (int)Math.pow(th, x);
+            if (p > n) {
+                break;
+            }
+            for (int i = n; i >= p; i--) {
+                dp[i] += dp[i - p];
+            }
+        }
+        return (int)(dp[n] % 1000000007);
+    }
+}

Codes/2787-ways-to-express-an-integer-as-sum-of-powers.py

@@ -0,0 +1,18 @@
+'''
+Author: LetMeFly
+Date: 2025-08-12 09:48:56
+LastEditors: LetMeFly.xyz
+LastEditTime: 2025-08-12 21:37:06
+'''
+class Solution:
+    def numberOfWays(self, n: int, x: int) -> int:
+        dp = [1] + [0] * n
+        th = 1
+        while True:
+            p = th ** x
+            if p > n:
+                break
+            th += 1
+            for i in range(n, p - 1, -1):
+                dp[i] += dp[i - p]
+        return dp[-1] % 1000000007

Codes/2787-ways-to-express-an-integer-as-sum-of-powers.rs

@@ -0,0 +1,23 @@
+/*
+ * @Author: LetMeFly
+ * @Date: 2025-08-12 09:48:56
+ * @LastEditors: LetMeFly.xyz
+ * @LastEditTime: 2025-08-12 22:00:07
+ */
+impl Solution {
+    pub fn number_of_ways(n: i32, x: i32) -> i32 {
+        let n: usize = n as usize;
+        let mut dp: Vec<i32> = vec![0; n + 1];
+        dp[0] = 1;
+        for th in 1usize.. {
+            let p: usize = th.pow(x as u32);
+            if p > n {
+                break;
+            }
+            for i in (p..=n).rev() {
+                dp[i] = ((dp[i] as i64 + dp[i - p] as i64) % (1000000007 as i64)) as i32
+            }
+        }
+        dp[n]
+    }
+}

Codes/lib.rs

@@ -5,4 +5,4 @@
  * @LastEditTime: 2025-08-11 22:07:08
  */
 pub struct Solution;
-include!("0869-reordered-power-of-2_20250810.rs");  // 这个fileName是会被脚本替换掉的
+include!("2787-ways-to-express-an-integer-as-sum-of-powers.rs");  // 这个fileName是会被脚本替换掉的

README.md

@@ -870,6 +870,7 @@
 |2769.找出最大的可达成数字|简单|<a href="https://leetcode.cn/problems/find-the-maximum-achievable-number/" target="_blank">题目地址</a>|<a href="https://blog.letmefly.xyz/2024/05/21/LeetCode%202769.%E6%89%BE%E5%87%BA%E6%9C%80%E5%A4%A7%E7%9A%84%E5%8F%AF%E8%BE%BE%E6%88%90%E6%95%B0%E5%AD%97/" target="_blank">题解地址</a>|<a href="https://letmefly.blog.csdn.net/article/details/139101760" target="_blank">CSDN题解</a>|<a href="https://leetcode.cn/problems/find-the-maximum-achievable-number/solutions/2785705/letmefly-2769zhao-chu-zui-da-de-ke-da-ch-sb7w/" target="_blank">LeetCode题解</a>|
 |2779.数组的最大美丽值|中等|<a href="https://leetcode.cn/problems/maximum-beauty-of-an-array-after-applying-operation/" target="_blank">题目地址</a>|<a href="https://blog.letmefly.xyz/2024/06/15/LeetCode%202779.%E6%95%B0%E7%BB%84%E7%9A%84%E6%9C%80%E5%A4%A7%E7%BE%8E%E4%B8%BD%E5%80%BC/" target="_blank">题解地址</a>|<a href="https://letmefly.blog.csdn.net/article/details/139707025" target="_blank">CSDN题解</a>|<a href="https://leetcode.cn/problems/maximum-beauty-of-an-array-after-applying-operation/solutions/2811818/letmefly-2779shu-zu-de-zui-da-mei-li-zhi-9ywc/" target="_blank">LeetCode题解</a>|
 |2786.访问数组中的位置使分数最大|中等|<a href="https://leetcode.cn/problems/visit-array-positions-to-maximize-score/" target="_blank">题目地址</a>|<a href="https://blog.letmefly.xyz/2024/06/14/LeetCode%202786.%E8%AE%BF%E9%97%AE%E6%95%B0%E7%BB%84%E4%B8%AD%E7%9A%84%E4%BD%8D%E7%BD%AE%E4%BD%BF%E5%88%86%E6%95%B0%E6%9C%80%E5%A4%A7/" target="_blank">题解地址</a>|<a href="https://letmefly.blog.csdn.net/article/details/139688753" target="_blank">CSDN题解</a>|<a href="https://leetcode.cn/problems/visit-array-positions-to-maximize-score/solutions/2810990/letmefly-2786fang-wen-shu-zu-zhong-de-we-71a5/" target="_blank">LeetCode题解</a>|
+|2787.将一个数字表示成幂的和的方案数|中等|<a href="https://leetcode.cn/problems/ways-to-express-an-integer-as-sum-of-powers/" target="_blank">题目地址</a>|<a href="https://blog.letmefly.xyz/2025/08/12/LeetCode%202787.%E5%B0%86%E4%B8%80%E4%B8%AA%E6%95%B0%E5%AD%97%E8%A1%A8%E7%A4%BA%E6%88%90%E5%B9%82%E7%9A%84%E5%92%8C%E7%9A%84%E6%96%B9%E6%A1%88%E6%95%B0/" target="_blank">题解地址</a>|<a href="https://letmefly.blog.csdn.net/article/details/150296585" target="_blank">CSDN题解</a>|<a href="https://leetcode.cn/problems/ways-to-express-an-integer-as-sum-of-powers/solutions/3751207/letmefly-2787jiang-yi-ge-shu-zi-biao-shi-no5x/" target="_blank">LeetCode题解</a>|
 |2788.按分隔符拆分字符串|简单|<a href="https://leetcode.cn/problems/split-strings-by-separator/" target="_blank">题目地址</a>|<a href="https://blog.letmefly.xyz/2024/01/20/LeetCode%202788.%E6%8C%89%E5%88%86%E9%9A%94%E7%AC%A6%E6%8B%86%E5%88%86%E5%AD%97%E7%AC%A6%E4%B8%B2/" target="_blank">题解地址</a>|<a href="https://letmefly.blog.csdn.net/article/details/135724019" target="_blank">CSDN题解</a>|<a href="https://leetcode.cn/problems/split-strings-by-separator/solutions/2612832/letmefly-2788an-fen-ge-fu-chai-fen-zi-fu-s1dn/" target="_blank">LeetCode题解</a>|
 |2789.合并后数组中的最大元素|中等|<a href="https://leetcode.cn/problems/largest-element-in-an-array-after-merge-operations/" target="_blank">题目地址</a>|<a href="https://blog.letmefly.xyz/2024/03/14/LeetCode%202789.%E5%90%88%E5%B9%B6%E5%90%8E%E6%95%B0%E7%BB%84%E4%B8%AD%E7%9A%84%E6%9C%80%E5%A4%A7%E5%85%83%E7%B4%A0/" target="_blank">题解地址</a>|<a href="https://letmefly.blog.csdn.net/article/details/136698122" target="_blank">CSDN题解</a>|<a href="https://leetcode.cn/problems/largest-element-in-an-array-after-merge-operations/solutions/2685943/letmefly-2789he-bing-hou-shu-zu-zhong-de-jrx8/" target="_blank">LeetCode题解</a>|
 |2798.满足目标工作时长的员工数目|简单|<a href="https://leetcode.cn/problems/number-of-employees-who-met-the-target/" target="_blank">题目地址</a>|<a href="https://blog.letmefly.xyz/2024/04/30/LeetCode%202798.%E6%BB%A1%E8%B6%B3%E7%9B%AE%E6%A0%87%E5%B7%A5%E4%BD%9C%E6%97%B6%E9%95%BF%E7%9A%84%E5%91%98%E5%B7%A5%E6%95%B0%E7%9B%AE/" target="_blank">题解地址</a>|<a href="https://letmefly.blog.csdn.net/article/details/138352241" target="_blank">CSDN题解</a>|<a href="https://leetcode.cn/problems/number-of-employees-who-met-the-target/solutions/2762052/letmefly-2798man-zu-mu-biao-gong-zuo-shi-2sb8/" target="_blank">LeetCode题解</a>|